Is there a straight forward way to check whether an interaction should be used for HB modelling?
Theroretically I have 4 interactions between two variables. Not sure whether I should include it in HB or not.
For sure prct cert. increases from .58 to about .76 when i use the interactions but maybe this is due to overfitting?
So - without having some latent class software - how can I check whether it makes sense?